As it turns out, the A-list comedy writer-director-producer is collaborating with the animated series in front of the microphone as well. EW has learned that a different episode — which was already known to boast Will Arnett as a guest star — features the voices of Apatow, frequent collaborators Leslie Mann, Paul Rudd, and Seth Rogen, plus Channing Tatum and... Judas Priest frontman Rob Halford.

Fed up with movie theaters, Homer is taught by Bart how to illegally download films, and he starts screening them in his backyard for folks in Springfield. "Even though Homer is stealing, he's doing it for the community, he's doing it out of the goodness of his heart," says executive producer Matt Selman. Alas, an overzealous FBI director in charge of anti-piracy (Arnett) doesn't quite see it that way and sets his sights on Homer.

How do our celebrity guests fit into the plot? One of the movies that Homer shows is a This is 40-esque Apatow dramedy titled Life is Funny that stars Mann and Rudd, who joined forces in Knocked Up and This is 40. Halford winds up singing a parody of the Judas Priest classic "Breaking The Law" in an effort to nab Homer, while Apatow testifies against our patriarch "with a hilarious, self-important speech about Hollywood people," says Selman. Another Knocked Up star, Rogen, has a cameo role as himself, as does Tatum. "Channing Tatum loves to do surprise twists in movies, a la This is the End," hints Selman, "and he has a surprise twist in this one too."

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That's not the end of the movie-based madness. At the very end of the episode, adds Selman, "there is a crazy twist where Rudd returns in a super meta thing that people may or may not understand."

The Apatow & Friends showcase, which is titled "Steal This Episode," is slated to air in January. It marks a return visit to Springfield for Rudd and Rogen: Rudd guested in a season 22 episode and Rogen co-wrote the season 21 premiere and voiced a character.